光电一体化处理杀扑磷农药废水  

Treatment of methidathion pesticide wastewater by photoelectrocatalysis methods

作　　者：丛燕青[1] 马香娟 李玉琼[1] 吴祖成[1] 

机构地区：[1]浙江大学环境科学研究所,浙江杭州310027 [2]浙江工商大学食品生物与环境工程学院,浙江杭州310035

出　　处：《浙江大学学报（工学版）》2006年第4期647-651,共5页Journal of Zhejiang University：Engineering Science

基　　金：中国博士后科学基金资助项目(2005038290);浙江省自然科学基金资助项目(Z505060)

摘　　要：为了解决有机磷农药引起的严重环境污染问题,采用一种新的催化氧化方法———光电一体化高级氧化工艺,处理杀扑磷农药废水.实验表明,光电结合能有效地降低废水的化学需氧量(COD),与单独光催化和单独电催化相比,杀扑磷的降解效率大大提高,且存在协同作用,协同效率可达96%.加入少量电解质后,废水COD去除率迅速提高到80%以上.光电催化过程产生大量强氧化性羟基自由基(.OH),诱发链反应产生,杀扑磷被有效降解,生成小分子有机酸,导致溶液pH值降低.由于NaCl在电解中产生氧化能力较强的ClO-,加入NaCl电解质比加入Na2SO4能更好地降低废水的COD.不同初始浓度对降解效率有较大影响,杀扑磷农药废水的降解符合表观一级动力学方程.光电结合能有效降低杀扑磷废水的毒性,适于作为高浓度难降解废水的预处理过程.To resolve the problems of environmental pollution caused by organophosphorus pesticides, a new technology, photoeleetrocatalysis, was developed to treat methidathion pesticide wastewater. Experimental results showed that photoelectrocatalysis could effectively reduce COD of wastewater. Compared with single photocatalysis or single electrocatalysis, the degradation efficiency of photoelectrocatalysis was increased significantly and synergetic effects were obvious. The synergetic factor was 96% and COD removal rate was over 80%. Hydroxyl radicals （ · OH） generated in photoelectrocatalysis process could degrade methidathion to organic acids, which resulted in pH decrease of wastewater. NaCl was more effective electrolyte than Na2SO4. COD reduction of methidathion wastewater could be simplified to be pseudofirst-order reaction. Photoeleetroeatalysis methods can effectively decrease the toxicity of methidathion wastewater and can be used as a pretreatment method for refractory wastewater.

关 键 词：光催化 电催化 杀扑磷农药 光电催化 协同作用 

分 类 号：X522[环境科学与工程—环境工程]